In a chair in which a lumbar support is mounted on the backrest, the lumbar support comprises a body; a pair of connecting portion suspending from the lower ends of the sides; and a handle extending sideward of the lower end of the side edge of the connecting portion, the handle running through the side of the back frame or backrest body to enable a vertical position of the lumbar support to be adjusted by the handle in Patent Literature 1.
A lumbar support comprises a body; and a pair of operating portions suspending from the lower ends of the sides and having a knob extending sideward at the lower end in Patent Literature 2. The right and left sides of the body are supported by the bracket in side members to move vertically.
The lumbar support holding portion stands in the middle of the lower end of the back frame in Patent Literature 3. The lumbar support body is mounted in the middle on the lumbar support holding portion and adjusted in a vertical position.
Patent Literature 4 discloses that the vertical guide member along the backrest is mounted and the lumbar support is moved along the guide member.
Patent Literature 5 discloses that the lower end of the lumbar support is under a bent point of the backrest and the lumbar support is moved vertically.